Fluid-fuel-burner control



Oct. 8, 1929. s v s 1,730,829

FLUID FUEL BURNER CONTROL Filed May '7, 1927 INVENTOR Paul if [fin/era,

f ATTORNEYS Patented Oct. 8, 1929 UNITED STATES PATENT OFFICE PAUL F.SHIVERS, OF WA IBASH, INDIANA, ASSIGNOR, BY MESNE ASSIGNMENTS, TOMINNEAPOLIS-HONEYWELL REGULATOR. COMPANY, OF MINNEAPOLIS, MINNESOTA,

A CORPORATION OF DELAWARE FLUID-FUEL-BURNER CONTROL Application filedMay 7, 1927. Serial No. 189,481.

The object of my invention is to provide a' simple and efficient meansfor automatically controlling the action of a fluid-fuel burner so thatit may be depended upon to permit automatic normal operations of theburner but will prevent delivery of fuel in all cases of accidentalfailure of ignition or combustion, the construction being such that highvoltage currents will be available for the fuel motor and ignition meansand low voltage currents will be available for the room thermostat, warpswitches and circuit breakers sensitive to combustion conditions.

The accompanying drawing illustrates my invention diagrammatically, highvoltage circuits being shown in heavy lines and low voltage circuitsbeing shown in light lines.

In the drawings 10 and 11 indicate the power leads, 12 the primary oftransformer T and 13 and 14 connections between said primary and thepower leads 10 and 11.

The burner motor M is electrically connected by wire 15 to one terminal16 of a motor-actuated circuit breaker S and to one terminal 17 of anignition circuit breaker IS.

Said motor Mis also connected by wire 18 with lead 10.

Paired with terminal 16 is a terminal 20 in one end of a mercury tube 21carried by the pivotally supported body 22 of switch S, said body beingreciprocated by a plunger 23 which controls a fuel valve 24 in the fuelsupply line, said plunger 23 being actuated in one direction by areducing train 25 from the rotor 26 of the supplemental valve motor VM.Plunger 23 is biased against the action of the rotor by a spring 27.Terminal 20 is connected by wire 19 with lead 11.

Paired with terminal 17 is a terminal 30 in one end of a mercury tube 31carried by a pivoted carrier 32 of the ignition switch IS.

Said carrier 32 is biased to circuit-breaking means 36 and electricalpilot gas valve 37 which are connected by wire 38 with lead 10.

, The secondary 40 of transformer T is connected by wire 41 with one endof the stator 42 of the valve motor VM, the opposite end of said statorbeing connected by wire 43 w th the leaf 44 of a warp switch W, saidleaf being normally held in electrical contact with terminal 45 againstthe bias of spring 46. Electrically insulated from leaf 44 of the warpswitch W is a bi-metallic blade 47 which normally holds leaf 44 incontact with terminal 45. Electrically connected to blade 47 is one endof a heating coil 48, the opposite end of which is connected by wire 49with terminal 45. A wire 50 connects heating coil 48 and terminal 45with a terminal 51 in the hot end of a mercury tube 52 which is part ofa combustion control element G which. is sensitive to combustionconditions adjacent the burner.

Paired with terminal 51 is a terminal 53 which is electrically connectedwith a terminal 54 in' the cold end of tube 52 and terminals 53 and 54are connected by wire 55 with blade 47.

Paired with terminal 54 in the cold end of tube 52 is a terminal whichis connected by wire 61 with a terminal 62 adapted to be contacted by amovable terminal 63 which is under the influence of plunger 23. Terminal63 is connected by a wire 64 with wire 55 and therefore with blade 47and terminals 53 and 54. The room thermostat R has one side connected bya wire with wire 41 and through that wire to secondary 40 and stator 42.The other side of the room thermostat R is connected by wire 71 with theheating coil 72 of a warp switch we, said coil being connected to thebi-metallic blade 73 of said warp switch which blade is connected bywire 74 with secondary 40 of transformer T. The blade 73 iscold-separated from terminal 7 5 of the warp switch w and. said terminalis connected by wire 76 with wire 61 and therefore with terminals 60 and62.

The operation is as follows:

. The diagram shows the parts in cold position.

Upon demand for heat at R the circuit 40-4 7 4-7 37271R7 O-4140 ifclosed with suificient definiteness at the room thermostat R, will causea Warping of blade 73 to close contact of said blade with terminal 75,thus establishing the circuit 40-74-48- 7576-61605455474849 454443424140, thus energizing the supplemental motor VM to shift plunger25'to open fuel valve 24, shift circuit breaker S to circuit-closingposition, and release ignition switch IS.

Connection of terminals 16-20 completes the fuel motor circuit11192016-15- M1810. Connecton of terminals 1620 also completes theignition circuit 11-19 20-16151730.35- 36 37 38 10 and in due course,dependent upon the ad justment of the dash-pot D, circuit breaker ISopens the ignition circuit at 17-30.

The opening movement of plunger 23 also moves terminal 63 into contactwith terminal 62 and thereby shorts out the cold side of the combustioncontrol C providing for motor VM the circuit 40-4142434445 494847556463626 176 7 5 7 37440, the shunt circuit 7 0R7 2 being maintained tokeep coil 7 2 heated and thus mainta-n the contact 7 3-75.

If ignition of the fuel takes place within the time interval before theignition circuit breaker IS moves to circuit breaking position, thecombustion control C will move to hop position, thus breaking thecircuit at 54 and making a circuit at 51 53, thus providing4041-424344454950 51 53-55-64636261767573- 74 40 which maintains currentin the stator of the supplemental motor VM and shunts out the heatingcoil 48 of the warp switch NV.

The apparatus remains in this condiiton so long as proper combustion ismaintained at the burner and the room thermostat R calls for heat.

Upon break at the room therinostat R the supplemental motor VM isdenergized and spring 27 returns valve 24, circuit breakers S and IS andterminal 63 to initial position, whereupon fuel delivery isdiscontinued.

If combustion fails for any reason the combustion control returns to thecold position, thus returning the heating coil 48 into the supplementalmotor circuit, whereupon, in the course of predetermined time the warpswitch 1V is actuated and the circuit of the supplemental motor isbroken at 4445 and manual reset is necessary to put the apparatus incommission.

The warp switch w is not an absolute essential in this constructionbecause the room thermostat B may be substituted for it, but theprovision of the warp switch w eliminates some objections which flowfrom a fluttering of the room thermostat.

While I have illustrated mercury tube switch s a a io s p i s it will bereadi y understood that any desired form of circuit breaker suitable forhandling the necessary current may be substituted Without departing frommy invention. It will also be understood that the details of motor VMand its connection with the switches actuated thereby may beconsiderably modified and thatit is not absolutely essential that thismotor actuates a fuel; valve because, while such a valve is quitedesirable to insure against leakage of fuel past the fuel deliveringapparatus driven or controlled by motor M, such apparatus controlled bymotor M may be solely relied upon to control the flow of fuel.

For convenience motor M may be called the fuel motor and motor VM may becalled the supplemental motor. The details of the warp switch may bevaried, the essential characteristic being that there be a retardedcircuitbreaking action after a predetermined time interval of currentflow in the absence of combustion at the burner, and the term warpswitch in the claims is used to designate such a device generally, andthe term heating coil is used to designate generally the element thereofelectrically causing delayed circuitbreaking action. 0

The fuel motor maydrive or control a fuel pump or other fuel-flowcontrol means and may drive movable parts of the burner proper.

The term room thermostat is used to designate a main circuit-controllingelement sensitive to thermal or other conditions to be affected by theburner.

These various details may be Varied through a wide range withoutdeparting from my invention.

The details of construction of the fuel valve forms the subject matterof my ,co-pending application Serial No. 111,154.

I claim:

1. In a control system for fluid-fuel burners, aburner. motor; asupplemental motor; a circuit-breaker actuated by said supplementalmotor and comprising a pair of terminals; a circuit-breaker sensitive tocombustion conditions adjacentthe burner and comprising a cold-pair ofterminals and a hot-pair of terminals; a warp switch comprising aheating coil; a transformer; electrical connections from powerto oneterminal of the motor-actuated circuit-breaker and from power to fuelmotor; electrical connections from power to the motor-actuated circuitbreaker; electrical connections from the motor-actuated circuit-breakerto the fuel motor; electrical connections from the transformer secondaryto the supplemental motor, the warp switch and its heating coil, and toone terminal of both the hot and cold pairs of terminals of thecircuit-breaker sensitive to combustion conditions adjacent the burner;

electrical connections between the warp jcircuit-breaker actuated bysaid supplemental motor and comprising a pair of terminals; electricalignition mechanism; a delayed-action circuit-breaker biased to'openposition; one-way actuating mechanism controlled by the supplementalmotor for moving theignition circuit-breaker to normal closed position;a circuit-breaker sensitive to combustion conditions adjacent the burnerand comprising a cold-pair of terminals and a hot-pair of terminals; awarp switch comprising a heating coil; a transformer; 4 electricalconnections from power to one terminal of the motor-actuatedcircuit-breaker, from power to fuel motor, and from power to ignitionmeans; electrical connections from ignition means to the delay-actioncircuit breaker; electrical connections from ignition circuit breaker tothe motor-actuated circuit breaker; electrical connections from themotor-actuated circuitbreaker to the fuel motor; electrical connectionsfrom the transformer secondary to the supplemental motor, the warpswitch and its heating coil, and to one'terminal of both the hot andcold pairs of terminals of the circuitbreaker sensitive to combustionconditions adjacent the burner; electrical connections between the warpswitch, its heating coil, and

the other terminal of the hot-pair of the circuit-breaker sensitive tocombustion conditions adjacent the burner whereby said circuit-breakerin the hot position will shunt out said heating coil; electricalconnections between the warp switch, warp switch heatmg coil andtransformer secondary, compris ing two separable terminals one of which.

is moved to andfrom its fellow by said supplemental motor; and a roomthermostat connected to the transformer secondary to control flow ofcurrenttlirough said secondary.

3. In a control system for fluid fuel burners. a burner motor; asupplemental motor; a reciprocable member controlled by the supplementalmotor; means biasing said reciprocable member in opposition to thesupplemental motor; a circuit-breaker actuated by said reciprocablemember and comprising a pair of terminals; a circuit-breaker sensitiveto combustion conditions adjacent the burner and comprising a cold-pairof terminals and a hot-pair of terminals; a warp switch com- PIlSlIlg aheatlng 0011; a transformer; electrical connections from power to oneterminal of the motor-actuated circuit-breaker, from power to fuelmotor; electrical connections from power to the motor-actuated circuitbreaker; electrical connections from the motor-actuated circuit-breakerto the fuel motor; electrical connections from the transformer secondaryto the supplemental motor, the warp switch and its heating coil, and toone terminal of both the hot and cold pairs 7 of terminals of thecircuit-breaker sensitive to combustion conditions adjacent the burner;electrical h connections between the warp switch, its heating coil, andthe other terminal of the hot-pair of the circuit-breaker sensitive tocombustion conditions adjacent the burner whereby said circuit-breakerin the hot posi-' tion will shut out said heating coil; electricalconnections between the warp switch, warp switch heating coil andtransformer Sec- 25 ondary, comprising terminals controlled by saidreciprocable member; and a room thermostat connected to the transformersec ondary to control flow of current through said secondary.

4. In a control system for fluid-fuel burners, a burner motor; asupplemental motor; a reciprocable member actuated by said supplmentalmotor in one direction means biasing said reciprocable member inopposition as to the supplemental motor; a circuit-breaker actuated bysaid reciprocable member and comprising a pair of terminals; electricalignition mechanism; a delayed-action circuitbreaker biased to openposition; one-way actuating mechanism controlled by the reciprocablemember for moving the ignition circuit-breaker to normal closedposition; a circuit-breaker sensitive to combustion conditions adjacentthe burner and comprising a cold-pair of terminals and a hot-pair ofterminals; a warp switch comprising a heating coil; a transformer;electrical connections from power to one terminal of the motoractuatedcircuitbreaker, from power to fuel motor, and from power to ignitionmeans;

velectrical connections from ignition means to.

the delay-action circuit breaker; electrical connections from lgnitioncircuit breaker to the motor-actuated circuit breaker; electricalconnections from the motor-actuated circuitbreaker to the fuel motor;electrical connections from the transformer secondary to thesupplemental motor, the warp switch and its heating coil, and to oneterminal of both 12 the hot and cold pairs of terminals of thecircuit-breaker sensitive to combustion conditions adjacent the burner;electrical connections between the warp switch, its heating coil, andthe other terminal of the hot-pair of the circuit-breaker sensitive tocombustion conditions adjacent the burner whereby said circuit-breakerin the hot position will shunt out said heating coil; electricalconnections between the warp switch, warp switch heating 0 coil andtransformer secondary, comprising terminals controlled by saidreciprocable member; and a room thermostat connected to the transformersecondary to control flow of current through said secondary.

5. A control system having the characteristics specified in claim 1,wherein the room A arranged to control flow of current to thesupplemental motor. 7

8. A control system having the characteristics specified in claim 3wherein the room thermostat is in circuit with a warp switch arranged tocontrol flow of current to the sup- I Q plemental motor.

9. A control system having the characteristics specified in claim iwherein the room thermostat is'in circuit with a warp switch arranged tocontrol flow of current to the supplemental motor.

10. A control system having the characteristics specified in claim 2 andwherein a fuel valve, controlled by the supplemental motor, controlsflow of fuel relative to the burner.

.11. A control system having the characteristics specified in claim 3and wherein a fuel valve, controlled by the supplemental motor, controlsflow of fuel relative to the burner.

12. A control system having the character-' istics specified in claim 4and wherein a fuel valve, controlled by the supplemental motor,

controls flow of fuel relative to the burner.

In witness whereof, I, PAUL F. SHIVERS,

have hereunto set my hand at Wabash, In-

diana, this 30th day of April, A. D. one

thousand nine hundred and twenty-seven. 1.

PAUL F. SHIVERS.

cram-mare or comcrrcit" ram No. 1,730,829. I Granted October a, 1929-,to

, ram. F. smvERs.

It is hereby certified that error ap I r I pears n the printed specifcation of the aboveinumbered patent requiring correction as follows:Page 3, line 83, claim 3, for the word "shut" read "shunt"; and that thesaid Letters Patent should be read with this correction therein that thes ame may conform to the of the case In the Patent Office. record Signedand sealed this 5th day of November, A. D. 1929.

M. J. Moore,

.(Seal) Acting Commissioner of Patents.

